Description

The erase() and werase() routines copy blanks to every position in the
window.

The clear() and wclear() routines are like erase() and werase(), but they
also call clearok(), so that the screen is cleared completely on
the next call to wrefresh() for that window and repainted from scratch.

The clrtobot() and wclrtobot() routines erase all lines below the cursor in
the window. Also, the current line to the right of the cursor,
inclusive, is erased.

The clrtoeol() and wclrtoeol() routines erase the current line to the right
of the cursor, inclusive.

Return Values

All routines return the integer OK, or a non-negative integer if immedok()
is set. See curs_outopts(3CURSES).